<template>
  <div class="header">
    <!-- 折叠按钮 -->
    <div class="collapse-btn" @click="collapseHandle">
      <i class="el-icon-menu"></i>
    </div>
    <!-- LOGO -->
    <div class="logo">后台管理系统</div>
    <!-- 右边 -->
    <div class="header-right">
      <!-- 用户信息 -->
      <div class="header-user-con">
        <!-- 全屏 -->
        <div class="btn-fullscreen">
          <el-tooltip effect="dark" :content="fullscreen?`取消全屏`:`全屏`" placement="bottom">
            <i class="el-icon-rank"></i>
          </el-tooltip>
        </div>
        <!-- 消息 -->
        <div class="btn-bell">
          <el-tooltip effect="dark" :content="messages?`有${messages}未读消息`:`消息中心`" placement="bottom">
            <router-link to="/tabs">
              <i class="el-icon-bell"></i>
            </router-link>
          </el-tooltip>
          <span class="btn-bell-badge" v-if="messages"></span>
        </div>
        <!-- 头像 -->
        <div class="user-avator">
          <img src="../assets/img/user.jpg"/>
        </div>
        <!-- 用户下拉菜单 -->
        <el-dropdown class="user-name">
          <span class="el-dropdown-link">
            {{username}} <i class="el-icon-caret-bottom"></i>
          </span>
          <el-dropdown-menu slot="dropdown">
            <a href="http://blog.gdfengshuo.com/about/" target="_blank">
              <el-dropdown-item>关于作者</el-dropdown-item>
            </a>
            <a href="https://github.com/lin-xin/vue-manage-system" target="_blank">
              <el-dropdown-item>项目仓库</el-dropdown-item>
            </a>
            <el-dropdown-item divided command="logout">退出登录</el-dropdown-item>
          </el-dropdown-menu>
        </el-dropdown>
      </div>
    </div>
  </div>
</template>

<script>
  export default {
    name: "Header",
    data() {
      return {
        collapse: false,
        fullscreen: false,
        messages: 2,
        username: 'zhangsanw'
      }
    },
    methods: {
      collapseHandle() {
        this.collapse = !this.collapse;
        this.$bus.$emit('collapse', this.collapse);
      }
    }
  }
</script>


<style scoped>
  .header {
    position: relative;
    box-sizing: border-box;
    width: 100%;
    height: 70px;
    font-size: 22px;
    color: #fff;
  }

  .collapse-btn {
    float: left;
    padding: 0 21px;
    cursor: pointer;
    line-height: 70px;
  }

  .header .logo {
    float: left;
    width: 250px;
    line-height: 70px;
  }

  .header-right {
    float: right;
    padding-right: 50px;
  }

  .header-user-con {
    display: flex;
    height: 70px;
    align-items: center;
  }

  .btn-fullscreen {
    transform: rotate(45deg);
    margin-right: 5px;
    font-size: 24px;
  }

  .btn-bell, .btn-fullscreen {
    position: relative;
    width: 30px;
    height: 30px;
    text-align: center;
    border-radius: 15px;
    cursor: pointer;
  }

  .btn-bell-badge {
    position: absolute;
    right: 0;
    top: -2px;
    width: 8px;
    height: 8px;
    border-radius: 4px;
    background: #f56c6c;
    color: #fff;
  }

  .btn-bell .el-icon-bell {
    color: #fff;
  }

  .user-name {
    margin-left: 10px;
  }

  .user-avator {
    margin-left: 20px;
  }

  .user-avator img {
    display: block;
    width: 40px;
    height: 40px;
    border-radius: 50%;
  }

  .el-dropdown-link {
    color: #fff;
    cursor: pointer;
  }

</style>
